How much pasture is needed per cow?
This time of year, we're all wondering how fast to move the animals over the pasture. This question came from a reader:
Hi Beth and Shawn, I attended one of your rotational grazing course a last summer and had great success. I had to mix things up a bit due to when I started, equipment available, time, etc. This spring I’m able to truly move everyone every day! My question is for 20 cow calf pairs (some are heavy bred, some have calves, a bull, and some are early bred, but to make math simple let’s call them 20 units), ranging in size from 800-2000 pounds, what is a recommended square foot per unit? I have it at about 900 square feet per cow/calf unit right now but could change it if I needed to. I don’t want to push it to hard because it was a crop field for decades and this is the first year it will be rotational for the entire year. We gave it a rest after October due to drought last summer.I’d really appreciate your feedback
Hi, Amber! Great to hear from you.
This is a terrific question . Where are you? And at what stage of forage growth? How you want to graze is completely dependent on what your pastures are growing.I’m assuming you are at least a little south of zone 6, because around here people are just now putting animals out. We’re usually among the first in our neck of the woods, and we went onto green grass about three weeks ago.The issue of how much space to give your animals is a function of how fast you think your grass is growing, and how much residual you are trying to leave, as well as how many animals and acres you’re managing. (The acres are probably a fixed number — I assume what you have is what you have.) In early spring, when the grass is just coming on, we’re seldom actually looking at the grass we’ll be grazing in three weeks — it hasn’t grown yet — we’re calculating on what we think will be grown in three weeks, right? And we don’t want to mess that guess up too badly and then find we’ve got to either overgraze where we are, or get back to our first paddock too soon. Ouch, either way.In spring our paddocks are huge, so we don’t hit them too hard. Consequently we’re moving over the pasture very quickly, which will bring us back to where we started very quickly, too. We’re watching to see that there is plenty of residual in each paddock when we leave, and checking the paddocks already grazed to see that we aren’t moving up on them too fast.We run Jersey and Jersey/cross cows and calves — paired and otherwise — and count 800 lb. as our unit weight. In May, all things being equal, they’ll be on about 320 sq. ft. of pasture per animal, which makes them something comparable to your larger animals on 900 sq. ft. of a less productive pasture. So far, so good.Right now, though, we’re running around the farm on paddocks something like five or six times the size they’ll be in May — maybe 1500 sq.ft. per unit per day. That’ll get us around the farm in three or four weeks total. It’s a juggling act, to build paddocks as big as possible without getting so big that the animals can be choosy and selective. We’re looking for paddocks with no really hard grazing lines, and enough leaf mass for regrowth.That said, when we started managing our grass ten or twelve years ago, we hit it hard in the spring, with small paddocks. Maybe it wasn’t ideal, but by the time we got around the pasture those early paddocks had had plenty of time to recover! Furthermore, you yourself might like to graze harder on your recovering pasture if what you’re hitting is perennial weeds — set them back now, and let the grass have time to move in.All of this is to share our thought processes with you, not to give advice, though. If there is one thing this farming teaches us, it’s that there are lots of permutations to every decision, and lots of paths to a desirable end. What I would say most emphatically is that if you are there, moving fence every day, the grass and cows are going to teach you more than any expert or book could hope to. You’re almost guaranteed success.
Blessings!